I asked Professor Chauncey, after whom Nathan Lane's character in the play, Chauncey Miles, is named, why gay life in New York had been visible during the 1920s and early 1930s, but had become less so by 1937, when "The Nance" takes place. He replied that Prohibition, which lasted from 1919 to 1933, was an important factor. "Prohibition brought visibility to gay life. It pushed all of nightlife underground." There was, he continued, "a popular revolt against the moral order imposed by Prohibition. People became more interested in exploring new things."

White audiences, for example, flocked to Harlem to see African-American entertainers. And in the late 1920s and early 1930s, there was a "pansy craze," in which performers who acted stereotypically gay appeared at New York nightspots. "One of these real-life entertainers who I think Chauncey Miles is based on," Professor Chauncey said, "is Jean Malin. He started out as a female impersonator but by the time he was hired as the emcee at one of the top clubs in Times Square, in the early 30s, he was no longer doing drag." Chauncey continued: "Malin was a very big guy, and could take care of himself physically. He became a bit of a hero at the time for many gay men: he was completely out there as a pansy entertainer but he wouldn't take abuse. If he was heckled, he sliced the heckler up with a razor-sharp wit."

The end of Prohibition affected gay visibility. "Its repeal," Chauncey said, "introduced a more efficient regime of police surveillance. Nightlife became legal but club and bar owners had to get a license to serve. The newly formed state liquor authority announced that it would not allow bars or restaurants to serve or employ homosexuals." There were, the historian added, "periodic crackdowns and then, in the two years before the 1939 World's Fair, a major crackdown."

Chauncey pointed out that after the Second World War there was another escalation of enforcement. (The historian has researched this period as part of his upcoming sequel to "Gay New York," which will cover 1940 to the mid-1970s.) But, he observed, New York continued to have a vibrant gay scene. "There's a tension that you always have to keep in mind. On the one hand, there's a lot of policing, which 'The Nance' dramatizes. On the other, resistance and repression forced people to come up with other ways to find each other, and they did."

As that last comment indicates, Chauncey recently saw a performance of "The Nance," and, not long before that, sat down with its author in person. (They had exchanged emails prior to the face-to-face meeting.) I would never in a million years have put the historian on the spot by asking for a detailed assessment. It was more than enough for him to tell me that he liked "The Nance" very much.

Brendan Lemon is the American theater critic for the Financial Times and the editor of lemonwade.com